This post demonstrates the effects of running a Double Tagging VLAN Hopping attack against the ProxMox hypervisor environment. In this scenario there are two Cisco 2950 switches in between the attacker and the virtual network. The experiment was performed on seven different hypervisor/virtual network configurations in order to perform a systematic evaluation of the effects across all of the major enterprise level virtualization platforms. The following network diagram illustrates the configuration used for each of the experiments:

The following video walks through the attack process and results against a virtual machine hosted within the ProxMox hypervisor environment.